1. Field of the Invention
The present invention relates to a sputtering target for use in production of a high-resistance transparent conductive film having a resistivity of about (0.8–10)×10−3 Ωcm, and to a method for producing a high-resistance transparent conductive film from the sputtering target.
2. Background Art
Indium oxide-tin oxide (In2O3—SnO2 complex oxide, hereinafter referred to as “ITO”) film, which is a transparent conductive film having high visible light transparency and high electrical conductivity, finds a variety of uses including heat-generating film for preventing dew formation on liquid crystal displays or glass plates, and infrared beam-reflecting film.
When transparent conductive film is used in a flat panel display (FPD), a low-resistivity transparent conductive film having a resistivity of about 2×10−4 Ωcm is employed.
Meanwhile, a transparent conductive film employed as a resistance touch panel attached to displays such as the above FPD is required to exhibit high-resistance characteristics (e.g., sheet resistance of about 700 to 1,000 Ω) on the basis of the operation mechanism of the touch panel.
However, in order for an ITO film conventionally employed in FPDs to be used as a transparent conductive film for a touch panel, the thickness of the conductive film must be reduced considerably, raising a problem that sufficient touch panel strength fails to be ensured.
Also, when the resistance of an ITO sputtering target itself is increased, a DC magnetron sputtering apparatus, which is inexpensive as compared with a high-frequency magnetron sputtering apparatus, cannot be employed. Thus, facility cost increases enormously, raising another problem.